East biding tire



Oct. 5, 1943. J. v. MARTIN EASY RIDING TIRE Filed Dec. 31, 1940 3 Sheets-Sheet-l all :l

O ct. 5, 1943. J. v. MARTIN 2,331,212

' EASY RIDING TIRE i Filed Dec. 5l, 1940 3 Sheets-Sheet 2 msx RIDING TIRE u Filed Dec. 31, 19'40 s sheets-sheet s IN VEN TOR.

Afrox/VEZ Patented Oct. 5, 1943 EASY RIDING TIRE -James V. Martin, Rochelle Park, N. J.

Application December 31, 1940, Serial No. 372,628

In Great Britain January 8. 1940 9 Claims.

'I'he primaryl purposefof my invention is to T' provide an easier riding and safer type of tire and one which will not require a spare tire for change over on the road.

A further object is to provide a type of tire which will permit control of an automobile over rough roads at higher speeds than are possible with inflated tires and -a still further object is to provide a comparatively cool tire at high speeds.

Still further objects are to provide a iiexlble type of tire for climbing curbs or tracks at small angles and to hold and conform to the road while delivering less violence to the axles over bumps in the road. y

With the above in mind the still further objects of my invention will become apparent as one follows the following description reference being had to the several views of the drawings:

Fig. 1 shows a sector of my invention attached to a vehicle wheel; the view being in side elevation.

Fig. 2 is a view partly in section taken along the line 2-2 of Fig. 1.

Fig. 3 is a view reduced in size showing typical brake assembly such as one would see looking toward the inside of the wheel assembly of Fig. 2.

Fig. 4 is a View partly in section taken along the line 4-4 of Fig. 2 and omitting the brake assembly. l

Fig. 5 is a full scale cross sectional view of one of the composite fillers used'in my invention and Fig. 6 indicates how such a filler deilects under load: Fig. 5 is taken on the line 5-5 of Fig. 6. Fig. 7 is a sketch made from an imprint of my type tire on the road and under load.

Figs. 8 and 9 show the bracket 9 and its connections to the wheel I.

Proceeding now to the more detailed description of, my vinvention like numerals 'will refer to similar parts throughout the several views: I indicates an automobile wheel mounted on a hub portion 2 and located outwardly of a brake drum 3, while 4 indicates brake bands mounted on typical brake shoes 5 for inside type brakes while 6 indicates a hydraulic type of brake setting mechanism.

l indicates a back" plate which protects the braking mechanism and carries the journals 8- for the brake shoes.

9 indicates in dotted lines a transverse bracket secured to the disc wheel I at 9' and having a pivoted portion 9a which extends from the pin I0 and the pivot ii around the end of the brake drum 3 to a position inwardly of the brake assembly. I2 indicates' a button headed extension of the bracket 9 and I3 illustrates a rubber molded tire spoke molded to fit over the said bracket 9 and its button headed portions I2. A dotted line I3" indicates the radially outer end of the molded opening in the spoke I3 and dotted lines i3a indicate the radially outer ends of such molded openings radially outward of the button heads themselves.

The tire spoke i3 is of molded rubber and in addition to its radially inner part which has molded loops i4 formed to lit over the bracket 9 the spokes have thickened portions i5 which cross each other diagonally and a web portion i8 and lateral beads il and outer lugs I8, as well as an outer bead I9. The outer or tread portion of my tire is made upof 3 tread hoops 20 in three different forms and each said hoop is united to the spokes of my tire by lugs 2i, which intermesh with the spoke lugs i8 and both sets of lugs are held in a constant interlocking position by means of a pin 22, made in its central portion of light steel tubing into which is press fitted at each end an aluminum button head 23 whichv fits into a molded aperture in each spoke end lug I8'. A hickory pin may be substituted for 22 and 23. All parts of the spokes are protected from curb contacts by lying inwardly laterally of the outer-v most portions of the tread envelope, see 25 in Fig. 2. v l

Each tread hoop has a core or filler 2l which is cured to and within a rubber envelope 25 and this carries a tread 26 ribbed circumferentially for the center hoop and a transversely ribbed tread 21 for the outer hoops: It will be noted that these outer hoops can be molded in the same mold and turned so that their curved portions lie toward the lateral margins of the tire. The curved and cross ribbed treadsl facilitate climbing curbs and car tracks at small angles and when a load is applied unevenly to the three tread hoops. each hoop is free to assume a different position within the limits ofthe rubber lugs I8 and 2l and the pin 22 in those lugs; for illustration see Fig. 25 of my Patent No. 2,283,274, issued May 19, 1942.

The fillers cured within my tire hoops are of special construction designed to give them great flexibility combined with great strength and the ability to flex often under heavy loads without breaking through flexing fatigue.

All of the axle loads are carried in tension through the upper spokes of my tire to the tread hoops through the flexible lugs and the fillers carry these loads flexibly down to the ground.

Each of my rubber spokes I3 is assembled onto the vehicle wheel under initial tension more than sufilcient to care for the static loads: Furthermore the slotted construction of the inner portions Il of my spokes prevents them from taking any compression loads even in severe bumps.

The initial tension of my spokes adds greatly to the strength of my fillers 24 because under road loadings the Weakest positions of my hoops is about half way from the ground to the tops of the said hoops. In Fig. 6 G indicates the ground or road and a broken line 28 indicates a true circle around the point 29: The other two lines indicate one of my flllers'24 under normal working loads and it will be observed that toward the top of the circle 'the outside of the filler 24 is curved about the same as the true circle, but bulges outwardly toward the horizontal diameter and lower down in spite of the inward pull exerted by the initially tensioned spokes and when the filler approaches the ground it takes a shape which conforms to the ground for a considerable distance, thus forming a fiat plane ground contact of considerable area. Fig. 7 is a sketch made from an actual imprint of one of my tires under load: 30 indicates the separation lines between the hoops. And the hollow spaces 3|, molded into the rubber envelopes help to make a firm wedging of the contacting treads so that no stones enter at the lines 30.

In order to secure a strong,vlight and yet exible filler for my tires I resort to construction illustrated in Fig. 5. This shows at approximately full scale a filler for a 28 inch outside diameter tire of about 6 inch width. Starting from the upper layer of ,the ller as shown in Fig. 5, which is the inside layer of the filler, I show a steel band a of approximately 315" thickness, this is cured securely to xls" layer b of rubber which prevents its crinkling under compression loads and it must be remembered that at the horizontal diameter of the ller, see Fig. 6, the point of highest loading, the compression loads are on the insides of the fillers or at a, while the highest tension loads are on the outsides of the fillers or at k of Fig. 5. k is also of high grade steel and well bonded to 11s" of rubber i. The intermediary layers or plies c, e, g. and i are of fibrous material such as hickory and a special latex bonding material is used to make sure the rubber layers or plies b. d, f, h and i are cured thereto by a strong bond.

The amount of ground bearing surface desired in the tire can be regulated by the amount of rubber between the layers of wood and steel together with the number of spokes employed, their amount of initial tension and whether hard or softer rubber compounds be employed. Also the softness of the compounds employed between the layers of hickory have an appreciable effect on the fillers flexibility.

Hickory may be used either solid and steam bent into a filler or laminated from hickory strips with casein glue or other forms of bond, but I find that the outer layers of hickory, i. e., for example, tend to fracture in tension at the horizontal diameter through 29 of Fig. 6 and by bonding a very thin (I show 1i4") band k of spring steel to rubber outside the hickory the breaking is greatly retarded or entirely stopped depending on the life desired for the fillers. The relatively thicker steel on the inside of each hoop ller, see a in Fig. 5, is better adapted to resist the crinkling of thin steel under compression loads but the bonding of the steel to rubber prevents this crinkling. especially if the compression and tension members of a steel truss are disposed as shown in Fig. 5, i. e., having the tension member and the compression member (latter too light by itself) spaced apart by such material as hickory, and firmly bonded to each other through intervening rubber of virtual tread rubber consisteney. The trick or art" in such a truss consists of regulating the compound and thickness of rubber backed by just enough wood to obtain maximum yieldable strength for weight and mass of material. In other words, if the layer of rubber is made too thick or too soft, even with good bonding it will not prevent fatal crinkling of the compression member of the truss: Also the rubber-steel combination on the tension or (k) side of the truss must be adapted by proximity, toughness and bonding to prevent the fracture from tension of the brillose material which spaces the steel truss members apart: The strongest possible truss structure would call for a wood to wood lamination with strong glue in the layers d. f. and h; the next best strength/weight ratio can be obtained by omitting layers d, f. and h of rubber and using steam bent hickory as the spacer, but to provide for a very flexible filler the form shown permits a radial movement of one hickory layer relative the others because of the interposed rubber, and increasing the amount of rubber or the softness of its compounding aids the flexibility.

It will be seen that larger ybrake diameter are made possible by my novel tire spoke attachments to the vehicle wheel, which allows a comparatively large vertical spoke flexibility for the tire and at the same time allows large brake diameters while producing a fanning air action to cool the brakes. For additional information respecting elastic spoke tires reference should be had to my Patents Nos. 1,954,214, 2,016,095, 2,050,352, and to my copending applications Serial Nos. 236,103, filed October 20, 1938. and issued as Patent No. 2,283,274, and 27,603, led June 20, 1935, and issued as Patent No. 2,235,378, as well as 319,539, led February 17, 1940, and issued October 6, 1942, as Patent No. 2,298,142.

The wheel I, see Fig. 2, is readily demountable in conventional manner, but before attempting its removal from the hub-brake assembly the pins I0 should be pulled out of the brackets 9 thus allowing the inner part 9a of these brackets to swing outwardly around the pivot II under the initial tension influence of the spoke I3: The center of the spoke I3 is`easily bendable and in this way all obstruction to demounting the wheel can be eliminated while leaving a very large diameter brake assembly undisturbed and attached to the vehicle hub.

It will be evident that my invention can be applied in various ways and I do not care to be limited to the specific embodiment used herein to illustrate the invention.

What I claim is:

1. A tire, wheel and brake assembly including a union between the said tire and wheel, the said brake located radially beyond and laterally between the inner portions of the said tire.

2. A tire, wheel and brake assembly according to claim l and spokes having diagonally crossed parts and having inner bifurcated portions, one such portion of each spoke located laterally on one side of the said brake assembly and the other of such spoke portions located symmetrically on the other side of the said brake assembly.

3. A vehicle wheel, tire and brake drum combination wherein the brake drum and wheel are attached to a wheel hub and the inner portions 'of the said tire are attached to the said wheel at points laterally on both sides of the said drum and less distant from the said hub than the most distant points of the said drum;` and means l of the said spokes.

5. A tire carrying its loads through Atension members from the upper portions of exible tread hoops and means located at the radially and laterally outer portions of the said tension members to connect the same with the tread hoops, each of the said hoops capable of a limited yieldable upward movement relative an adjacent hoop in the region of ground contact and having a curved contour fromtheground contacting portion to positions laterally beyond the said tension -member connections, whereby an outer of the said hoops can climb a curb by a limited independent movement relative an adjacent hoop and serve as a protection against curb contact for the said tension member connection.

6. The combination in an elastic spoke type tire, of flexible tread hoops lying outwardly oi and attached to the said spokes, a composite .1111er within a tread envelope of each said hoop y and said filler including bands-ot `steel each lbonded to rubber and spaced apart from each other by alternate layers of wood and rubber, the said steel being substantially thinner than `either the said layers of wood or rubber and bonded to a layer of rubber.

7. In combination with a tire tread a filler therefor including two comparatively thin bands of steel spaced apart from each other by alternate layers of rubber and ilbrillose material. each said layer of rubber bonded to an envelope surrounding the said bands of steel and said brillose material.

8. In combination with a vehicle wheel and tire, a tread hoop adapted toI carry loads from the said wheel delivered to its upper portion.

through tension members, said hoop including a laminated filler of alternate layers of rubber and wood composing the central portion thereof and two comparatively thin bands of-steel bonded within and surrounded by rubber and forming the innermost and outermost laminations o! the said 1111er.

9. 'Ihe combination in a tire tread hoop of a -illler madeup in its central portion of layers of wood bonded to comparatively thinner layers of rubber and an outermost layer of very thin metal bonded to one of the said layers of rubber, the said filler located within a tread envelope.

JAMES V. MARTIN. 

